• Journal of the Korean Geographical Society
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• v.39 no.6 s.105
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• pp.845-862
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• 2004

The aim of this study is to investigate distribution characteristics of incised meander cutoff in Gyeonggi and Gangwon Provinces of Central Korea. The density of meander cutoff is highest in the mountain rivers including Naerin and Dongdae flowing on Jeongseon-gun and Inje-gun of Gangwon Province. Most of meander cutoff process has been occurred repeatedly during the Quaternary period, especially concentrated in the period of climatic change between glacial and interglacial stages. In the aspect of the lithology, the density of cutoff is highest in sedimentary rock, but lowest in igneous rock. As for geological structure, its frequency is high at $11{\sim}20km$ westerly away from the Taebaek Mountains, at subsequent channel, lower part of resequent channel, and channels crossing the fault line. The relation between distance from the Taebaek Mountains and altitude is very obvious at the western side of the Taebaek Mountains. The values of altitude, height from riverbed, and stream order are highest at sedimentary rock and lowest at volcanic rock.

• Journal of the Korean Geographical Society
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• v.46 no.3
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• pp.304-318
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• 2011

The types, distributional and shape properties of abandoned channels in Korea are classified and examined. There are 409 abandoned channels in Korea and they can be classified into the 6 types such as the incised meander cutoff, stream piracy, distributary, artificial incised meander neck-cutoff, channel straightening of free meander and distributary streams. The abandoned channels by incised meander neck-cutoff showing the most frequency with 266, have the topographical properties of high altitude and steep relief and frequently distribute in Gangwon and Gyeonbuk Province and in the upper reaches of main stream of Nakdong-River, and Dal-River and Pyeongchang-River, tributaries of Namhan-River. The most frequency areas of abandoned channels by distributary, channel straightening of free meander and distributary streams are the lower reaches of Namhan-River and main stream in the lower reaches of Nakdong-River, Mangyeong-River and Yeongsan-River, and Geumho-River, respectively. The abandoned channles by incised meandering neck-cutoff and stream piracy are relatively used as farmlands or forests due to the high altitude and relative altitude from the river bed.

• Journal of The Geomorphological Association of Korea
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• v.19 no.2
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• pp.1-15
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• 2012

The formative ages and processes of five natural abandoned channels in three types in Korea are studied. The former meandering channel in Seongsandong, Uljin-gun was abandoned due to the neck-cutoff of incised meander, Wangpi River in approximately 2.5~2.6ka and the abandoned channel in Bulyeong Temple, Uljin-gun was formed by the neck-cutoff of Wangpi River in approximately 90ka. Deduced from these results, it is judged to favorable for formation of abandoned channels by incised meander cutoff in interglacial or interstadial stages that had a better condition for meander cutoff because of active lateral erosion. Due to the corrosion of limestone joints in the underground of ridges between Hwangji River and Cheolam River, the channel in Gumumso, Taebaek-si was abandoned by the stream piracy connecting and combining the rivers into a limestone cave in approximately 40ka and higher lower reaches of Dong River than Banbyeon River in Seonbawi, Yeongyang-gun was turned to the abandoned channel throughout the stream piracy between the rivers in approximately 1.4ka. During Last Glacial Maximum in Jangcheon-ri, Chungju-si, Namhan River was divided into the eastern and western tributaries due to the alluvial island in approximately 10ka and then the western tributary was abandoned recently.

• Journal of the Korean Geographical Society
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• v.48 no.5
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• pp.615-628
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• 2013

The waterfall can be formed by difference between the height of up and down part in new channel, is formed by channel avulsion that rapidly changing of river channel course. This study described types and processes of waterfalls by channel avulsion, and analyzed rates and factors of waterfall recession, on object to 7 waterfalls in South Korea. Bulyeong falls at Uljin-gun, Yongchu falls at Yeongdeok-gun, Jikyeon falls at Yanggu-gun and Gwangpum falls at Uljin-gun are formed by natural incised meander cutoff. Samhyeongje falls at Taebaek-si and Guryong falls are formed by river capture processes, and Palbong falls at Chungju-si is formed by artificial channel cutting for farm land secured. The locations of waterfalls gradually moved to upstream over time by head erosion. The recession rates were measured by 3~4m/ka on Bulyeong falls, Yongchu falls, Jikyeon falls and Samhyeongje falls, to estimate of formation age. Recession rates of these 4 waterfalls were analyzed that have clearly positive correlations with drainage area, precipitation, corrosion and weathering capability of bedrock, and initial height of waterfall.

• Journal of Navigation and Port Research
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• v.30 no.5 s.111
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• pp.331-334
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• 2006

In this paper, we designed and fabricated the lowpass filter with the wide stopband characteristics using microp- strip line. Adding the $\lambda_g/4$ open stub at the input and output ports, we developed the L-C ladder type lowpass filter using the open stub which has wide stopband characteristics. In order to reduce the entire size qf this filter, the high impedance microstrip lines were made with the meander structure. The lowpass filter was fabricated with the cutoff frequency 2.3 GHz and its measured frequency responses agree well with the simulation results.

• Journal of the Korean association of regional geographers
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• v.14 no.4
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• pp.279-289
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• 2008

The purpose of this paper is to search for geomorphological landscape resources of Goryeong-gun, to provide fundamental data for their management through mapping their distribution, and to present their conservation and application plan. The results are as follow: Firstly, geomorphological landscape resources in mountain area are Misungsan and Jusan mountain of Goryeong-up, Sangbiri valley of Deoggok-myeon, and isolated hill of Gaejin-myeon. Secondly, geomorphological landscape resources in riparian area are natural wetlands such as Jinchonneup of Bu-ri Gaejin-myeon, Hochonneup and Dalseongseupji of Hochon-ri Dasan-myeon, Bongsanneup of Bongsan-ri Ugok- myeon; artificial wetlands following the construction of weir such as riparian wetland of Oe-ri Goryeong-up and Banun-ri Gaejin-myeon; meander core and abandoned channel of Banun-ri Gaejin -myeon, river cliffs such as Naegok-ri Goryeong-up and Weolo-ri Ugok-myeon; sand bars and braided channel of Yajeong-ri Ugok-myeon. Thirdly, Jinchonneup swamp area of Bu-ri Gaejin-myeon have characteristics of typical floodplain landform, and its conservation conditions is relatively satisfactory, and its accessibility to metropolis is great, so it is a good place to construct eco-park. And construction of inquiry learning place at Banun-ri Gaejin-myeon will increase the opportunity to observe environmental changes following incised meander cutoff and ecological affirmative functions of a weir.